diff --git a/class/cdc/usbd_cdc_ecm.c b/class/cdc/usbd_cdc_ecm.c
index 86198f92..d9be91d4 100644
--- a/class/cdc/usbd_cdc_ecm.c
+++ b/class/cdc/usbd_cdc_ecm.c
@@ -157,6 +157,30 @@ void cdc_ecm_int_in(uint8_t ep, uint32_t nbytes)
     }
 }
 
+uint8_t *usbd_cdc_ecm_get_tx_buffer(void)
+{
+    return g_cdc_ecm_tx_buffer;
+}
+
+int usbd_cdc_ecm_start_write(uint32_t length)
+{
+    if (g_cdc_ecm_tx_data_length > 0) {
+        return -USB_ERR_BUSY;
+    }
+
+    g_cdc_ecm_tx_data_length = length;
+
+    USB_LOG_DBG("txlen:%d\r\n", g_cdc_ecm_tx_data_length);
+    return usbd_ep_start_write(cdc_ecm_ep_data[CDC_ECM_IN_EP_IDX].ep_addr, g_cdc_ecm_tx_buffer, g_cdc_ecm_tx_data_length);
+}
+
+void usbd_cdc_ecm_start_read_next(void)
+{
+    g_cdc_ecm_rx_data_length = 0;
+    g_cdc_ecm_rx_data_buffer = NULL;
+    usbd_ep_start_read(cdc_ecm_ep_data[CDC_ECM_OUT_EP_IDX].ep_addr, g_cdc_ecm_rx_buffer, CDC_ECM_MAX_PACKET_SIZE);
+}
+
 #ifdef CONFIG_USBDEV_CDC_ECM_USING_LWIP
 struct pbuf *usbd_cdc_ecm_eth_rx(void)
 {
@@ -167,16 +191,14 @@ struct pbuf *usbd_cdc_ecm_eth_rx(void)
     }
     p = pbuf_alloc(PBUF_RAW, g_cdc_ecm_rx_data_length, PBUF_POOL);
     if (p == NULL) {
+        usbd_cdc_ecm_start_read_next();
         return NULL;
     }
     memcpy(p->payload, (uint8_t *)g_cdc_ecm_rx_buffer, g_cdc_ecm_rx_data_length);
     p->len = g_cdc_ecm_rx_data_length;
 
     USB_LOG_DBG("rxlen:%d\r\n", g_cdc_ecm_rx_data_length);
-    g_cdc_ecm_rx_data_length = 0;
-    g_cdc_ecm_rx_data_buffer = NULL;
-    usbd_ep_start_read(cdc_ecm_ep_data[CDC_ECM_OUT_EP_IDX].ep_addr, g_cdc_ecm_rx_buffer, CDC_ECM_MAX_PACKET_SIZE);
-
+    usbd_cdc_ecm_start_read_next();
     return p;
 }
 
@@ -201,8 +223,7 @@ int usbd_cdc_ecm_eth_tx(struct pbuf *p)
 
     g_cdc_ecm_tx_data_length = p->tot_len;
 
-    USB_LOG_DBG("txlen:%d\r\n", g_cdc_ecm_tx_data_length);
-    return usbd_ep_start_write(cdc_ecm_ep_data[CDC_ECM_IN_EP_IDX].ep_addr, g_cdc_ecm_tx_buffer, g_cdc_ecm_tx_data_length);
+    return usbd_cdc_ecm_start_write(g_cdc_ecm_tx_data_length);
 }
 #endif
 
diff --git a/class/cdc/usbd_cdc_ecm.h b/class/cdc/usbd_cdc_ecm.h
index 8381b1a5..9859fe7c 100644
--- a/class/cdc/usbd_cdc_ecm.h
+++ b/class/cdc/usbd_cdc_ecm.h
@@ -14,17 +14,23 @@ extern "C" {
 
 /* Ethernet Maximum Segment size, typically 1514 bytes */
 #define CONFIG_CDC_ECM_ETH_MAX_SEGSZE 1514U
-#define CONFIG_USBDEV_CDC_ECM_USING_LWIP
 
 /* Init cdc ecm interface driver */
 struct usbd_interface *usbd_cdc_ecm_init_intf(struct usbd_interface *intf, const uint8_t int_ep, const uint8_t out_ep, const uint8_t in_ep);
 
 /* Setup request command callback api */
 void usbd_cdc_ecm_set_connect_speed(uint32_t speed[2]);
-void usbd_cdc_ecm_data_recv_done(void);
+
+/* Api for eth only without any net stack */
+uint8_t *usbd_cdc_ecm_get_tx_buffer(void);
+void usbd_cdc_ecm_send_done(void);
+int usbd_cdc_ecm_start_write(uint32_t length);
+void usbd_cdc_ecm_data_recv_done(uint8_t *buf, uint32_t len);
+void usbd_cdc_ecm_start_read_next(void);
 
 #ifdef CONFIG_USBDEV_CDC_ECM_USING_LWIP
-#include <lwip/pbuf.h>
+#include "lwip/netif.h"
+#include "lwip/pbuf.h"
 struct pbuf *usbd_cdc_ecm_eth_rx(void);
 int usbd_cdc_ecm_eth_tx(struct pbuf *p);
 #endif
diff --git a/demo/cdc_ecm_template.c b/demo/cdc_ecm_template.c
index 8eb6d03f..87300078 100644
--- a/demo/cdc_ecm_template.c
+++ b/demo/cdc_ecm_template.c
@@ -221,7 +221,7 @@ void cdc_ecm_lwip_init(void)
     // while (dnserv_init(&ipaddr, PORT_DNS, dns_query_proc)) {}
 }
 
-void usbd_cdc_ecm_data_recv_done(void)
+void usbd_cdc_ecm_data_recv_done(uint8_t *buf, uint32_t len)
 {
 }